Taking the Temperature on MarsThe Heat Flow and Physical Properties Probe, HP3 for short, burrows down to almost 16 feet (five meters) into Mars' surface. That's deeper than any previous arms, scoops, drills or probes before it. Like studying the heat leaving a car engine, it measures the heat coming from Mars' interior to reveal how much heat is flowing out of the body of the planet, and what the source of the heat is. This helps scientists determine whether Mars formed from the same stuff as Earth and the Moon, and gives them a sneak peek into how the planet evolved.
- Main Job: HP3 takes Mars' temperature, revealing just how much heat is still flowing out of the interior of the planet.
- Location: Mounted on the lander deck at launch. Upon landing, the lander's arm picks up HP3 and places it on the surface. The mole then hammers itself under the surface.
- Mass: Just over 6.5 pounds (about 3 kilograms)
- Power: A maximum of 2 watts while burrowing underneath the surface.
- Volume: About 5.3 gallons (20 liters) in total
- Data Return: 350 megabits over the course of the mission
Did You Know?HP3 digs deeper than all previous arms, scoops, drills or probes that have ever studied Mars!
How It WorksLike studying the heat leaving a car engine, HP3 will study the heat coming out of Mars, to shed light on what's producing the heat. It will tell scientists whether Earth and Mars are made of the same stuff, and how heat flows inside Mars.
How Heat Escapes MarsPlanets have heat within them, and some, like the Earth for example, are hotter than others, such as Mars. Hot elements that were present in the material that first formed the planet, and energy left over from the process of planet formation, are the fuel that produces this heat. It gives rise to magnetic fields, mountains, and movement in the crust, which causes quakes. HP3 studies the heat escaping from Mars to determine how fast the "engine" of the planet is running and what's fueling it.
HP3 buries down to almost 16 feet (5 meters) to ensure its measurements remain unaffected by the changes in the seasons. Every 1.5 feet (50 centimeters) the probe puts out a pulse of heat and its sensors watch how the heat pulse changes with time. If the crust material is a good conductor of heat, like metal, the pulse will decay quickly. If it is a poor conductor, like glass, the pulse will decay slowly. This tells scientists how quickly the temperature increases with depth, and how heat flows inside Mars.